<?php
// Exit if accessed directly.
if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Opaljob_API Class
 *
 * Renders API returns as a JSON/XML array
 *
 * @since  1.1
 */
class Opalestate_API_Admin {
	/**
	 * Latest API Version
	 */
	const VERSION = 1;
	/**
	 * Pretty Print?
	 *
	 * @var bool
	 * @access private
	 * @since  1.1
	 */
	private $pretty_print = false;
	/**
	 * Log API requests?
	 *
	 * @var bool
	 * @access public
	 * @since  1.1
	 */
	public $log_requests = true;
	/**
	 * Is this a valid request?
	 *
	 * @var bool
	 * @access private
	 * @since  1.1
	 */
	private $is_valid_request = false;
	/**
	 * User ID Perpropertying the API Request
	 *
	 * @var int
	 * @access public
	 * @since  1.1
	 */
	public $user_id = 0;
	/**
	 * Instance of Opalestate Stats class
	 *
	 * @var object
	 * @access private
	 * @since  1.1
	 */
	private $stats;
	/**
	 * Response data to return
	 *
	 * @var array
	 * @access private
	 * @since  1.1
	 */
	private $data = [];
	/**
	 *
	 * @var bool
	 * @access public
	 * @since  1.1
	 */
	public $override = true;

	/**
	 * Render Sidebar
	 *
	 *    Display Sidebar on left side and next is main content
	 *
	 * @return string
	 * @since 1.0
	 *
	 */
	public static function get_instance() {

		static $_instance;
		if ( ! $_instance ) {
			$_instance = new Opalestate_API_Admin();
		}

		return $_instance;
	}

	/**
	 * Setup the Opalestate API
	 *
	 * @since  1.1
	 * @access public
	 */
	public function __construct() {
	    if ( is_admin() ) {
	        $this->register_actions();
        }
	}

	/**
	 * Registers query vars for API access
	 *
	 * @access public
	 * @param array $vars Query vars
	 *
	 * @return string[] $vars New query vars
	 * @since  1.1
	 *
	 */
	public function register_actions() {
		add_action( 'admin_init', [ $this, 'process_action' ] );
		add_action( 'show_user_profile', [ $this, 'user_key_field' ] );
		add_action( 'edit_user_profile', [ $this, 'user_key_field' ] );
		add_action( 'personal_options_update', [ $this, 'update_key' ] );
		add_action( 'edit_user_profile_update', [ $this, 'update_key' ] );
		add_action( 'opalestate_action', [ $this, 'process_api_key' ] );

		// Setup a backwards compatibility check for user API Keys
		add_filter( 'get_user_metadata', [ $this, 'api_key_backwards_compat' ], 10, 4 );
		// Determine if JSON_PRETTY_PRINT is available
		$this->pretty_print = defined( 'JSON_PRETTY_PRINT' ) ? JSON_PRETTY_PRINT : null;
		// Allow API request logging to be turned off
		$this->log_requests = apply_filters( 'opalestate_api_log_requests', $this->log_requests );
	}

	/**
	 * Registers query vars for API access
	 *
	 * @access public
	 * @param array $vars Query vars
	 *
	 * @return string[] $vars New query vars
	 * @since  1.1
	 *
	 */
	public function process_action() {
		if ( isset( $_REQUEST['opalestate_action'] ) ) {
			$args = [
				'user_id'                => isset( $_REQUEST['user_id'] ) ? sanitize_text_field( $_REQUEST['user_id'] ) : 0,
				'key_permissions'        => isset( $_REQUEST['key_permissions'] ) ? sanitize_text_field( $_REQUEST['key_permissions'] ) : 'read',
				'description'            => isset( $_REQUEST['description'] ) ? sanitize_text_field( $_REQUEST['description'] ) : '',
				'opalestate_api_process' => isset( $_REQUEST['opalestate_api_process'] ) ? sanitize_text_field( $_REQUEST['opalestate_api_process'] ) : '',
			];

			do_action( 'opalestate_action', $args );
		}
	}

	/**
	 * Retrieve the user ID based on the public key provided
	 *
	 * @access public
	 * @param string $key   Public Key
	 *
	 * @return bool if user ID is found, false otherwise
	 * @since  1.1
	 * @global WPDB  $wpdb  Used to query the database using the WordPress
	 *                      Database API
	 *
	 */
	public function get_user( $key = '' ) {
		global $wpdb, $wp_query;

		if ( empty( $key ) ) {
			$key = urldecode( $wp_query->query_vars['key'] );
		}

		if ( empty( $key ) ) {
			return false;
		}

		$user = get_transient( md5( 'opalestate_api_user_' . $key ) );

		if ( false === $user ) {
			$user = $wpdb->get_var( $wpdb->prepare( "SELECT user_id FROM $wpdb->usermeta WHERE meta_key = %s LIMIT 1", $key ) );
			set_transient( md5( 'opalestate_api_user_' . $key ), $user, DAY_IN_SECONDS );
		}

		if ( $user != null ) {
			$this->user_id = $user;

			return $user;
		}

		return false;
	}

	public function get_user_public_key( $user_id = 0 ) {
		global $wpdb;

		if ( empty( $user_id ) ) {
			return '';
		}
		$cache_key       = md5( 'opalestate_api_user_public_key' . $user_id );
		$user_public_key = get_transient( $cache_key );

		if ( empty( $user_public_key ) ) {
			$user_public_key = $wpdb->get_var( $wpdb->prepare( "SELECT meta_key FROM $wpdb->usermeta WHERE meta_value = 'opalestate_user_public_key' AND user_id = %d", $user_id ) );
			set_transient( $cache_key, $user_public_key, HOUR_IN_SECONDS );
		}

		return $user_public_key;
	}

	public function get_user_secret_key( $user_id = 0 ) {
		global $wpdb;
		if ( empty( $user_id ) ) {
			return '';
		}
		$cache_key       = md5( 'opalestate_api_user_secret_key' . $user_id );
		$user_secret_key = get_transient( $cache_key );
		if ( empty( $user_secret_key ) ) {
			$user_secret_key = $wpdb->get_var( $wpdb->prepare( "SELECT meta_key FROM $wpdb->usermeta WHERE meta_value = 'opalestate_user_secret_key' AND user_id = %d", $user_id ) );
			set_transient( $cache_key, $user_secret_key, HOUR_IN_SECONDS );
		}

		return $user_secret_key;
	}

	/**
	 * Modify User Profile
	 *
	 * Modifies the output of profile.php to add key generation/revocation
	 *
	 * @access public
	 * @param object $user Current user info
	 *
	 * @return void
	 * @since  1.1
	 *
	 */
	public function user_key_field( $user ) {
		if ( ( opalestate_get_option( 'api_allow_user_keys', false ) || current_user_can( 'manage_opalestate_settings' ) ) && current_user_can( 'edit_user', $user->ID ) ) {
			$user = get_userdata( $user->ID );
			?>
            <hr class="clearfix clear">
            <table class="property-table">
                <tbody>
                <tr>
                    <th>
						<?php esc_html_e( 'Opalestate API Keys', 'opalestate-pro' ); ?>
                    </th>
                    <td>
						<?php
						$public_key = $this->get_user_public_key( $user->ID );
						$secret_key = $this->get_user_secret_key( $user->ID );
						?>
						<?php if ( empty( $user->opalestate_user_public_key ) ) { ?>
                            <input name="opalestate_set_api_key" type="checkbox" id="opalestate_set_api_key" value="0"/>
                            <span class="description"><?php esc_html_e( 'Generate API Key', 'opalestate-pro' ); ?></span>
						<?php } else { ?>
                            <strong style="display:inline-block; width: 125px;"><?php esc_html_e( 'Public key:', 'opalestate-pro' ); ?>&nbsp;</strong>
                            <input type="text" disabled="disabled" class="regular-text" id="publickey" value="<?php echo esc_attr( $public_key ); ?>"/>
                            <br/>
                            <strong style="display:inline-block; width: 125px;"><?php esc_html_e( 'Secret key:', 'opalestate-pro' ); ?>&nbsp;</strong>
                            <input type="text" disabled="disabled" class="regular-text" id="privatekey" value="<?php echo esc_attr( $secret_key ); ?>"/>
                            <br/>
                            <strong style="display:inline-block; width: 125px;"><?php esc_html_e( 'Token:', 'opalestate-pro' ); ?>&nbsp;</strong>
                            <input type="text" disabled="disabled" class="regular-text" id="token" value="<?php echo esc_attr( $this->get_token( $user->ID ) ); ?>"/>
                            <br/>
                            <input name="opalestate_set_api_key" type="checkbox" id="opalestate_set_api_key" value="0"/>
                            <span class="description"><label for="opalestate_set_api_key"><?php esc_html_e( 'Revoke API Keys', 'opalestate-pro' ); ?></label></span>
						<?php } ?>
                    </td>
                </tr>
                </tbody>
            </table>
		<?php }
	}

	/**
	 * Process an API key generation/revocation
	 *
	 * @access public
	 * @param array $args
	 *
	 * @return void
	 * @since  1.1
	 *
	 */
	public function process_api_key( $args ) {
		if ( ! wp_verify_nonce( $_REQUEST['_wpnonce'], 'opalestate-api-nonce' ) ) {
			wp_die( esc_html__( 'Nonce verification failed.', 'opalestate-pro' ), esc_html__( 'Error', 'opalestate-pro' ), [ 'response' => 403 ] );
		}
		if ( empty( $args['user_id'] ) ) {
			wp_die( esc_html__( 'User ID Required.', 'opalestate-pro' ), esc_html__( 'Error', 'opalestate-pro' ), [ 'response' => 401 ] );
		}

		if ( is_numeric( $args['user_id'] ) ) {
			$user_id = isset( $args['user_id'] ) ? absint( $args['user_id'] ) : get_current_user_id();
		} else {
			$userdata = get_user_by( 'login', $args['user_id'] );
			$user_id  = $userdata->ID;
		}
		$process = isset( $args['opalestate_api_process'] ) ? strtolower( $args['opalestate_api_process'] ) : false;

		if ( $user_id == get_current_user_id() && ! opalestate_options( 'allow_user_api_keys' ) && ! current_user_can( 'manage_opalestate_settings' ) ) {
			wp_die(
				sprintf(
				/* translators: %s: process */
					esc_html__( 'You do not have permission to %s API keys for this user.', 'opalestate-pro' ),
					$process
				),
				esc_html__( 'Error', 'opalestate-pro' ),
				[ 'response' => 403 ]
			);
		} elseif ( ! current_user_can( 'manage_opalestate_settings' ) ) {
			wp_die(
				sprintf(
				/* translators: %s: process */
					esc_html__( 'You do not have permission to %s API keys for this user.', 'opalestate-pro' ),
					$process
				),
				esc_html__( 'Error', 'opalestate-pro' ),
				[ 'response' => 403 ]
			);
		}

		switch ( $process ) {
			case 'generate':
				if ( $this->generate_api_key( $user_id ) ) {
					delete_transient( 'opalestate_total_api_keys' );
					wp_redirect( add_query_arg( 'opalestate-message', 'api-key-generated', 'edit.php?post_type=opalestate_property&page=opalestate-settings&tab=api_keys' ) );
					exit();
				} else {
					wp_redirect( add_query_arg( 'opalestate-message', 'api-key-failed', 'edit.php?post_type=opalestate_property&page=opalestate-settings&tab=api_keys' ) );
					exit();
				}
				break;
			case 'regenerate':
				$this->generate_api_key( $user_id, true );
				delete_transient( 'opalestate_total_api_keys' );
				wp_redirect( add_query_arg( 'opalestate-message', 'api-key-regenerated', 'edit.php?post_type=opalestate_property&page=opalestate-settings&tab=api_keys' ) );
				exit();
				break;
			case 'revoke':
				$this->revoke_api_key( $user_id );
				delete_transient( 'opalestate_total_api_keys' );
				wp_redirect( add_query_arg( 'opalestate-message', 'api-key-revoked', 'edit.php?post_type=opalestate_property&page=opalestate-settings&tab=api_keys' ) );
				exit();
				break;
			default;
				break;
		}
	}

	/**
	 * Generate new API keys for a user
	 *
	 * @access public
	 * @param int     $user_id    User ID the key is being generated for
	 * @param boolean $regenerate Regenerate the key for the user
	 *
	 * @return boolean True if (re)generated succesfully, false otherwise.
	 * @since  1.1
	 *
	 */
	public function generate_api_key( $user_id = 0, $regenerate = false ) {
		if ( empty( $user_id ) ) {
			return false;
		}
		$user = get_userdata( $user_id );
		if ( ! $user ) {
			return false;
		}
		$public_key = $this->get_user_public_key( $user_id );
		$secret_key = $this->get_user_secret_key( $user_id );

		if ( empty( $public_key ) || $regenerate == true ) {
			$new_public_key = $this->generate_public_key( $user->user_email );
			$new_secret_key = $this->generate_private_key( $user->ID );
		} else {
			return false;
		}

		if ( $regenerate == true ) {
			$this->revoke_api_key( $user->ID );
		}

		update_user_meta( $user_id, $new_public_key, 'opalestate_user_public_key' );
		update_user_meta( $user_id, $new_secret_key, 'opalestate_user_secret_key' );

		return true;
	}

	/**
	 * Revoke a users API keys
	 *
	 * @access public
	 * @param int $user_id User ID of user to revoke key for
	 *
	 * @return string
	 * @since  1.1
	 *
	 */
	public function revoke_api_key( $user_id = 0 ) {
		if ( empty( $user_id ) ) {
			return false;
		}
		$user = get_userdata( $user_id );
		if ( ! $user ) {
			return false;
		}
		$public_key = $this->get_user_public_key( $user_id );
		$secret_key = $this->get_user_secret_key( $user_id );

		if ( ! empty( $public_key ) ) {
			delete_transient( md5( 'opalestate_api_user_' . $public_key ) );
			delete_transient( md5( 'opalestate_api_user_public_key' . $user_id ) );
			delete_transient( md5( 'opalestate_api_user_secret_key' . $user_id ) );
			delete_user_meta( $user_id, $public_key );
			delete_user_meta( $user_id, $secret_key );
		} else {
			return false;
		}

		return true;
	}

	/**
     * Get version.
     *
	 * @return int
	 */
	public function get_version() {
		return self::VERSION;
	}

	/**
	 * Generate and Save API key
	 *
	 * Generates the key requested by user_key_field and stores it in the database
	 *
	 * @access public
	 * @param int $user_id
	 *
	 * @return void
	 * @since  1.1
	 *
	 */
	public function update_key( $user_id ) {
		if ( current_user_can( 'edit_user', $user_id ) && isset( $_POST['opalestate_set_api_key'] ) ) {
			$user       = get_userdata( $user_id );
			$public_key = $this->get_user_public_key( $user_id );
			$secret_key = $this->get_user_secret_key( $user_id );
			if ( empty( $public_key ) ) {
				$new_public_key = $this->generate_public_key( $user->user_email );
				$new_secret_key = $this->generate_private_key( $user->ID );
				update_user_meta( $user_id, $new_public_key, 'opalestate_user_public_key' );
				update_user_meta( $user_id, $new_secret_key, 'opalestate_user_secret_key' );
			} else {
				$this->revoke_api_key( $user_id );
			}
		}
	}

	/**
	 * Generate the public key for a user
	 *
	 * @access private
	 * @param string $user_email
	 *
	 * @return string
	 * @since  1.1
	 *
	 */
	private function generate_public_key( $user_email = '' ) {
		$auth_key = defined( 'AUTH_KEY' ) ? AUTH_KEY : '';
		$public   = hash( 'md5', $user_email . $auth_key . date( 'U' ) );

		return $public;
	}

	/**
	 * Generate the secret key for a user
	 *
	 * @access private
	 * @param int $user_id
	 *
	 * @return string
	 * @since  1.1
	 *
	 */
	private function generate_private_key( $user_id = 0 ) {
		$auth_key = defined( 'AUTH_KEY' ) ? AUTH_KEY : '';
		$secret   = hash( 'md5', $user_id . $auth_key . date( 'U' ) );

		return $secret;
	}

	/**
	 * Retrieve the user's token
	 *
	 * @access private
	 * @param int $user_id
	 *
	 * @return string
	 * @since  1.1
	 *
	 */
	public function get_token( $user_id = 0 ) {
		return hash( 'md5', $this->get_user_secret_key( $user_id ) . $this->get_user_public_key( $user_id ) );
	}

	/**
	 * API Key Backwards Compatibility
	 *
	 * A Backwards Compatibility call for the change of meta_key/value for users API Keys
	 *
	 * @param string $check     Whether to check the cache or not
	 * @param int    $object_id The User ID being passed
	 * @param string $meta_key  The user meta key
	 * @param bool   $single    If it should return a single value or array
	 *
	 * @return string            The API key/secret for the user supplied
	 * @since  1.3.6
	 *
	 */
	public function api_key_backwards_compat( $check, $object_id, $meta_key, $single ) {
		if ( $meta_key !== 'opalestate_user_public_key' && $meta_key !== 'opalestate_user_secret_key' ) {
			return $check;
		}

		$return = $check;

		switch ( $meta_key ) {
			case 'opalestate_user_public_key':
				$return = $this->get_user_public_key( $object_id );
				break;
			case 'opalestate_user_secret_key':
				$return = $this->get_user_secret_key( $object_id );
				break;
		}

		if ( ! $single ) {
			$return = [ $return ];
		}

		return $return;
	}
}